Alternator Help

Hi everyone, I've got yet another job that I have to do with my Corolla, and this time it's replacing the Alternator.

The voltage regulator failed the other night and the battery, which also happened to be dodgy, drained very quickly which meant I needed Roadside Assistance. I got a new battery from the Roadside Assistance guy, and had to drive for 30 minutes on a battery that wasn't charging due to the faulty regulator. I basically had everything off. Radio, fans, interior lights; all to conserve the battery charge.

I ordered a new Alternator today (same type, perfect for 4AFE engine), since I don't know how long it's been in the car, nor do I know how much longer it'll last for. Can't hurt to take some safety precautions. It'll show up on Monday, and until then I'm going to be doing as little driving as possible, and especially little to no driving at night.


With a Gregory's service book at my side, installing the Alternator should be a breeze, but I'm curious to know if anyone has any helpful suggestions, things to look out for, or tricks and tips to know when installing the Alternator.

I'll update the thread with progress and anything peculiar I come across.

Nothing really big to worry about, the alternator is the first belt on the crank so you don't have to take any others off, only real tricky bit is the tension and locking bolts, make sure you take note of how they go together and match it when putting the new one in.

Thanks Hiro. I got around to installing the new Alternator on Tuesday. I wasn't exactly sure how tight the belt was prior to removing the original Alternator, so I had a guess and drove around to see how it would bode.

Today I went back and released some of the tension on the belt, as turning the steering wheel close to full lock would cause some unwanted squeals and rattles, meaning that there may be too much (or too little) tension on the Power Steering drive belt. I'll look through the book to see if there's any explicit information on how tight the belt should be.

Honestly I was surprised that the removal and installation was as simple as that--remove three bolts, one nut and one plug and Bob's your uncle. Now that it's all good, I'll find out exactly what the tension should be so that the Power Steering drive belt runs perfectly.

without using any belt tension gauges, you simply press on the belt to see how much deflection it gives. Normally I just press the belt with the thumb and estimate if the deflection of the belt reaches more or less 1/2 inch, then I tighten the bolts.

sometimes you need to redo the belt tightening after running the belt so it seats properly, it may loosen a bit so you need to tighten it a bit more.

The other rough guide for belt tension is to try and twist it - it shouldn't turn more than ~90 degrees or so (from memory).

The other thing to be wary of too is that a belt stretches as it becomes used (generally a "used" belt is any one that has been run under load for any more than a few minutes), so you always need to re-adjust the tension after the first drive.